<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="./lib/jquery.js"></script>
    <style>
        .add{
            width: 400px;
            height: 400px;
            font-size: 30px;
            color: white;
        }
    </style>
</head>

<body>
    <div class="box">你是个天才</div>
</body>

</html>
<script>
    var obj = {
       fn:function(){
        $('.box').css('background','red')
        return obj
       },
       fn1:function(){
        $('.box').addClass('add')
        return obj
       },
       fn2:function(){
        $('.box').click(function(){
            alert('总能来点惊喜')
        })
       }
    };
    obj.fn().fn1().fn2()
</script>